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Organization and Summary of Significant Accounting Policies (Equipment Held of Operating Lease) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) engine | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Equipment Held for Operating Lease |  |  |
Impairment charge | $ 10,651 | $ 24,930 | $ 9,514
Minimum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 3 years |  |
Maximum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 39 years |  |
Engines and Related Equipment |  |  |
Equipment Held for Operating Lease |  |  |
Number of engines | engine | 34 |  |
Aircraft | Minimum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 13 years |  |
Residual value (as a percent) | 15.00% |  |
Aircraft | Maximum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 20 years |  |
Residual value (as a percent) | 17.00% |  |
Engines and aircraft |  |  |
Equipment Held for Operating Lease |  |  |
Equipment net book value | $ 46,300 |  |
Engines and aircraft | Minimum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 1 month |  |
Engines and aircraft | Maximum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 80 years |  |
New engine [Member] | Maximum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 25 years |  |
Equipment held for lease Member |  |  |
Equipment Held for Operating Lease |  |  |
Impairment charge | $ 5,300 | $ 4,400 |
Equipment held for lease Member | Engines and Related Equipment |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 15 years |  |
Residual value (as a percent) | 55.00% |  |
Equipment held for lease Member | Spare part packages |  |  |
Equipment Held for Operating Lease |  |  |
Residual value (as a percent) | 25.00% |  |
Equipment held for lease Member | Spare part packages | Minimum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 14 years |  |
Equipment held for lease Member | Spare part packages | Maximum |  |  |
Equipment Held for Operating Lease |  |  |
Estimated useful life | 15 years |  |
Equipment held for lease Member | Engines and aircraft |  |  |
Equipment Held for Operating Lease |  |  |
Impairment charge |  |  | $ 1,800

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- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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